Final answer:
The episodic buffer is the short-term memory component that combines information from long-term memory with working memory, playing a key role in integrating information for complex cognitive tasks.
Step-by-step explanation:
The component of short-term memory that combines information from long-term memory with the active processing in working memory is the episodic buffer. In the working memory model proposed by Baddeley and Hitch, the episodic buffer acts as a temporary storage system that integrates information across the other components of working memory (the visuospatial sketchpad and the phonological loop) with knowledge from long-term memory, providing a coherent, episodic representation. The central executive manages this process by directing attention and coordinating the activities of the working memory system, including the episodic buffer. The episodic buffer is capable of holding information from different sources and modalities, facilitating complex cognitive tasks such as reasoning and comprehension that require the integration of information.